package com.siss.tenancy.util;

import java.util.Random;

public class RandomUtil {
	// 生成随机数字和字母
	public static String getStringRandom(int length) {

		String val = "";
		Random random = new Random();

		// 参数length，表示生成几位随机数
		for (int i = 0; i < length; i++) {

			String charOrNum = random.nextInt(2) % 2 == 0 ? "char" : "num";
			// 输出字母还是数字
			if ("char".equalsIgnoreCase(charOrNum)) {
				// 输出是大写字母还是小写字母
				int temp = random.nextInt(2) % 2 == 0 ? 65 : 97;
				val += (char) (random.nextInt(26) + temp);
			} else if ("num".equalsIgnoreCase(charOrNum)) {
				val += String.valueOf(random.nextInt(10));
			}
		}
		return val;
	}
	
	/**
	 * 产生随机的四位数验证码
	 * 
	 * @return
	 */
	public static String getVerificationCode() {
		Random rad = new Random();

		String result = rad.nextInt(10000) + "";

		if (result.length() != 4) {
			return getVerificationCode();
		}
		return result;
	}

	/**
	 * 随机产生指定长度数字
	 *
	 * @return
	 */
	public static String getVerificationCode(Integer rendomLength) {
		Random rad = new Random();
		String result = rad.nextInt(10000) + "";
		if (result.length() != rendomLength) {
			return getVerificationCode();
		}
		return result;
	}
}
